There may be a case where the state of a stopped vehicle such as opening or closing a window, turning on or off a light, or locking or unlocking a door differs from a predetermined reference state. For example, patent literature 1 discloses the technology that transmits information indicating the vehicle state to a user's mobile terminal via a data relay station. This prior art can notify the user carrying a mobile terminal distant from the vehicle of failed manipulation on a vehicle window or door.
The above-mentioned prior art needs to use a mobile communication network via the data relay station and has a problem of increased communication costs. According to the above-mentioned prior art, the communication apparatus mounted on a vehicle is costly and the entire system including an intermediary data communication station is large-scale and costly.
Recently, there is a spreading use of the technology that uses a wireless communication line to communicably interconnect a vehicle communication device mounted on a vehicle with a mobile communication terminal carried by a user. The use of this technology can provide a less costly configuration that transmits information notifying failed manipulation on vehicular accessories (vehicle accessories) from the vehicle communication device to the mobile communication terminal without using the mobile communication network via the data relay station.
In this case, however, a distance between the vehicle communication device and the mobile communication terminal is much shorter than the prior art. This may cause a problem of accidentally transmitting information to the mobile communication terminal or disabling the communication due to a variation in the radio wave area for wireless communication depending on the circumference environment even if a user stays in the vehicle compartment or is located near the vehicle. When the user washes a vehicle, for example, the user may be located near the vehicle and may intentionally unlock the vehicle door. In such a case, it is inconvenient to notify a failure to lock the door. By contrast, it is also inconvenient to unsuccessfully notify the failed manipulation even though the user actually failed the manipulation.